Gabe announced that windows fails and he wants to go linux. So based of this, the console will be Linux based that either allows to run Windows based games, or, what I think Gabe is aiming at, urging the developers to make hardcore games for Linux. Either way, this will be the first time Valve is going into hardware (at least to my knowledge) so we'll see where this goes.......

All in all this is about integration and innovation :)

Or they're preparing to move into the console market through the Apple TV.

http://www.ubergizmo.com/2012/04/apple-meets-with-valve/